Project Abstract The federal earned income tax credit (EITC), the largest cash transfer program for low-earning workers in the United States, is an economic policy to reduce poverty. Each year, the program provides earning subsidies in the form of tax credits to certain workers based on their pretax earnings, marital status, and number of children. In 1986, Rhode Island enacted the first state EITC supplementing the federal program. By 2017, 29 states and the District of Columbia had created their own EITC. Most states offer refundable EITCs where any excess of the credit beyond the tax liability is paid as a refund; however, a few states only offer non-refundable EITCs where credit offsets tax liability but cannot convert to a refund. State EITCs are largely set as a flat percentage of the federal credit and range widely. The notable variability in the existence, type, and generosity of state EITCs has provided opportunities to examine various effects of these policies. Evidence has emerged on the impact of EITC on health and well-being; however, there is a striking dearth of research on the impact of EITC on violence. Our knowledge on whether, for whom, and why these policies are effective in preventing multiple forms of violence is severely limited. Guided by a specific Theory of Change model, we will leverage a ?natural experiment? through using the state policy variations resulting from the adoption and expansion of state EITCs over the past three decades to examine their impact on child maltreatment, youth violence, intimate partner violence, sexual violence, and suicide. We will use several administrative, surveillance, and survey data sources containing information on a variety of violence outcomes to address our aims over the period 1986-2017. As a multidisciplinary team of investigators with expertise in public health, public policy, and medicine, we will conduct a quasi-experimental study to: (1) Evaluate the magnitude of the impact of state EITCs existence, type, and generosity on the primary prevention of each of the five forms of violence, namely child maltreatment, youth violence, intimate partner violence, sexual violence, and suicide; (2) Explore whether the impact of state EITCs on these forms of violence differs by specific state-level and individual-level characteristics; and (3) Examine whether state EITCs influence specific shared risk and protective factors for these forms of violence, namely stress, parenting practices, material well-being, relationship quality, and financial independence. The proposed project will be the first comprehensive evaluation of the impact of state EITCs as a primary prevention strategy for multiple forms of violence. Considering the sheer burden of violence as a leading cause of mortality and morbidity in the United States, even a modest impact of state EITCs in preventing some forms of violence may translate to positive changes in a sizeable number of lives across the lifespan. Characterizing and quantifying this impact can further inform the adoption and expansion of current and future economic assistance policies to prevent violence and improve public health.